I was away for a bit last week, but I still keep up with the goings-on at home through social media, and I see growers all over the country are taking advantage of this weather to get some field work done. One of those field work operations being putting on some nitrogen, so I wanted to revisit the nitrification process one more time.
Three factors influence nitrification; moisture, temperature, and time. These three factors are always present and always influx, and that is what makes them dangerous and why there are models to help predict losses. The first two influence the amount the microbiological activity in the soil, which is the rate that ammonium is converted to nitrates. Time is the big one because it contains the gap between when those reactions start and when there are plants available to take up the nitrogen in the soil.
As I sit here writing my article today, I realize that we are about 60 days from the average start date of planting season. Also, I sit here, and the 4” soil temp is 44 degrees with a ten-day forecast that indicates soil temperatures will increase, and that makes time a dangerous foe. If you look at the chart below you will see that as temperature increases the acceleration of percent of nitrification over time changes almost exponentially.
You might be thinking to yourself “Where is he going with this?”. If you are one of those getting nitrogen applied I want you to consider again the use of a nitrogen stabilizer to protect your nitrogen investment. The soil isn’t going to stay 44 degrees for long and even if the soil cools it isn’t going to stay cool for long, and that puts nitrogen at risk for an extended amount of time. If it’s 60 days before we plant corn, it is closer to 120 days before the grand uptake of nitrogen starts by your corn plant, and if every pound of nitrogen lost is a bushel of corn we need to mitigate that risk.
The use of a nitrogen stabilizer “rents” us valuable time by either killing or slowing down the soil microbes from doing their jobs. Yes, it’s an added expense but the past two years yield data has shown that even in spring applications, using a nitrogen stabilizer has yielded about a 4.5-bushel advantage and an ROI of 1.7 in trials done right here in Nebraska.
For the most part, we can never “buy” time because it is the one thing that we will never have enough of, but in this situation, we must “rent” a little time because it is the one thing we will have too much of.